Preliminary Requirements

Procedure

1. SUBTASK 72-38-11-330-051 Remove the Inlet Cone Tip from the Inlet Cone Assembly

   1. Remove the inlet cone tip.

      1. Repair, VRS1462 TASK 72-38-11-300-002 (REPAIR-002).

2. SUBTASK 72-38-11-330-052 Remove the Polyurethane Coating

   1. Refer to Figure.

   2. Remove the polyurethane coating from the inlet cone.

      1. Mask the segments on the flange to prevent the contact of cold paint stripper.

         1. Use CoMat 02-005 ADHESIVE TAPE (MASKING).

      2. Soak the part into cold paint stripper for two hours.

         1. Use CoMat 01-040 COLD PAINT STRIPPER.

      3. Wash the inlet cone in clean cold water and dry using a clean dry air blast.

3. SUBTASK 72-38-11-380-062 Remove the Epoxy Varnish Coating

   1. Refer to Figure.

   2. 
      CAUTION
      THE DRY BLAST MUST NOT CONCENTRATE ON SAME AREA FOR MORE THAN TWO SECONDS.
      
      CAUTION
      WHEN REMOVING THE COATING ENSURE THAT THE PARENT FIBER CLOTH MATERIAL IS NOT EXPOSED. THIS REPAIR CANNOT BE PERFORMED IF THE PARENT FIBER CLOTH MATERIAL IS EXPOSED.

      NOTE

      This SUBTASK is an alternative to Step.

      Mask the areas which are not required coating.

      1. Use the CoMat 02-005 ADHESIVE TAPE (MASKING).

   3. Dry blast the area to be coated using aluminium oxide abrasive grit at air pressure 28.5 to 35.5 lb psi (196 to 245 Kpa) and distance 7.9 in. (200 mm) minimum between the part and blast nozzle.

      1. Use CoMat 05-026 DELETED.

4. SUBTASK 72-38-11-120-053 Remove the Epoxy Varnish Coating

   1. Refer to Figure.

   2. 
      CAUTION
      WHEN REMOVING THE COATING ENSURE THAT THE PARENT FIBER CLOTH MATERIAL IS NOT EXPOSED. THIS REPAIR CANNOT BE PERFORMED IF THE PARENT FIBER CLOTH MATERIAL IS EXPOSED.

      NOTE

      This SUBTASK is an alternative to Step.

      Mask the areas which do not require coating.

      1. Use the CoMat 02-005 ADHESIVE TAPE (MASKING).

   3. Remove the coating by hand.

      1. Use CoMat 05-019 WATERPROOF SILICON CARBIDE and CoMat 05-020 WATERPROOF SILICON CARBIDE.

      2. Carefully remove the paint to minimize removal of resin of the parent material.

5. SUBTASK 72-38-11-110-058 Clean the Surface after Removal of Coating

   1. Remove the dust.

      1. Use a clean dry air blast.

   2. Clean the surface of the parent material after removal of coating.

      1. Use CoMat 02-099 LINT-FREE CLOTH and CoMat 01-124 ISOPROPYL ALCOHOL.

6. SUBTASK 72-38-11-220-184 Examine the Surface after Removal of Coating

   1. Examine the surface of the parent material after removal of coating.

      1. Removal of resin of the parent material is permitted if the fiber cloth is not exposed. If the fiber cloth is exposed, reject the part.

7. SUBTASK 72-38-11-110-059 Clean the Surface for Repair

   1. Remove the dust.

      1. Use a clean dry air blast.

   2. Clean the area to be coated with a clean lint free cloth made moist with isopropyl alcohol.

      1. Use CoMat 02-099 LINT-FREE CLOTH and CoMat 01-124 ISOPROPYL ALCOHOL.

8. SUBTASK 72-38-11-380-052 Application of Epoxy Primer

   1. Refer to Figure.

   2. Mix the primer base and catalyst as following.

      1. Use the CoMat 07-080 TWO-PACK EPOXY PRIMER AND CATALYST and the CoMat 07-081 EPOXY PRIMER CATALYST epoxy primer catalyst.

         1. Epoxy primer base Parts by Volume 1.

         2. Epoxy primer catalyst Parts by Volume 1.

   3. NOTE

      If required, the CoMat 07-082 THINNERs may be added up to 10 per cent of volume.

      The mixture must be allowed to stand for 30 minutes prior to use.

      The pot life of mixed material is eight hours. If you do not use the mixture within eight hours, discard it.

      Apply the mixed compound to the area to be coated using brush or spray for minimized thickness as necessary.

   4. Cure the coating for 5 to 17 hours at room temperature. Alternatively it may be cured for one hour at room temperature followed by 30 minutes at 250 to 265 deg F (120 to 130 deg C) in oven. This coating will be coloured uniformly to yellow.

9. SUBTASK 72-38-11-380-053 Application of Epoxy Finish

   1. Refer to Figure.

   2. Mix the base and catalyst as following.

      1. Use the CoMat 07-079 BRIGHT ALUMINIUM and CoMat 07-007 TWO-PACK EPOXY FINISH (WHITE) AND CATALYST two-pack finish white and catalyst.

         1. Bright aluminum Parts by Volume 1.

         2. Catalyst Parts by Volume 1.

   3. NOTE

      If required, the CoMat 07-082 THINNERs may be added up to 10 percent of volume.

      The mixture must be allowed to stand for 30 minutes prior to use.

      The pot life of mixed material is eight hours. If you do not use the mixture within eight hours, discard it.

      Apply the mixed compound to the area to be coated areas using brush or spray for minimized thickness as necessary.

   4. Cure the coating for 5 to 17 hours at room temperature. Alternatively it may be cured for one hour at room temperature followed by 30 minutes at 250 to 265 deg F (120 to 130 deg C) in oven. This coating will be coloured uniformly to silver.

10. SUBTASK 72-38-11-380-054 Application of Polyurethane Coating

    1. Refer to Figure.

    2. Mix the elastmers as following.

       1. Use the CoMat 08-069 RESIN, CoMat 08-068 HARDENER and CoMat 01-076 METHYL ETHYL KETONE.

          1. Resin Parts by Weight 100.

          2. Hardner Parts by Weight 13.5.

          3. Methylethylketone Parts by Weight 40 to 70.

    3. NOTE

       The methylethylketone must be dried by adding 50 g of CoMat 01-082 SODIUM SULPHATE Na2SO4ANHYDROUS to 2.5 liters shaking well and allowing to stand 24 hours before decanting the supernatant liquid as required.

       Apply the mixed compound by spray gun and allow 10 to 30 minutes air-dry between coats. Apply one layer of 0.004 to 0.008 in. (0.1 to 0.2 mm) thickness on the coating area A followed by 0.004 in. (0.1 mm) thickness maximum on the coating area B.

    4. Dry the coated part for 30 minutes at room temperature.

    5. Do Step and Step again until a coat is achieved to the following thickness. Coating thickness on the area A is 0.02 in. (0.5 mm) minimum. Coating thickness on the area B is 0.005 in. (0.13 mm) minimum.

    6. Cure the final coat for two hours at 176 deg F (80 deg C) followed by four hours at 257 deg F (125 deg C) in oven.

11. SUBTASK 72-38-11-220-074 Examine the Coated Surface

    1. Refer to Figure.

    2. Visually examine the coated surface for scores, cracks and delaminations.

       1. Refer to TASK 72-38-11-200-000.

    3. Examine the diameter C and make sure it is contained within the given limit.

12. SUBTASK 72-38-11-360-051 Assemble the Inlet Cone Tip

    1. Assemble the inlet cone tip.

       1. Refer to Repair, VRS1462 TASK 72-38-11-300-002 (REPAIR-002).

13. SUBTASK 72-38-11-350-070 Identify the Repair

    1. Make a mark, VRS1466, adjacent to the part number.

       1. Use the ink method.

          1. Refer to SPM TASK 70-09-00-400-501.

Figure: Repair Details and Dimensions

Repair Details and Dimensions